The present invention relates to a magnet apparatus and an MRI (Magnetic Resonance Imaging) apparatus. Particularly, the present invention is concerned with a magnet apparatus using permanent magnets and an MRI apparatus which re-constructs an image on the basis of a magnetic resonance signal picked up through the magnet apparatus.
The MRI apparatus is constructed so as to re-construct an image on the basis of a magnetic resonance signal picked up through a magnet apparatus. A certain magnet apparatus uses a pair of parallel disc-like permanent magnets with magnetic poles of mutually opposite polarities opposed to each other through a spacing (see, for example, Patent Literature 1).
[Patent Literature 1]
Japanese Patent Laid Open No. 2002-369807 (p. 5-6, FIGS. 1 to 7)
The magnet apparatus of this type is suitable for the formation of a low magnetic field up to about 0.3T, but is not suitable for the formation of a medium magnetic field larger in field strength.